Apron clearers



Dec. 3, 1968 D ET AL. 3,413,677

APRON CLEARERS Filed Dec. 9, 1963 INVENTORS DAVID M. FORD ALFRED C. MORROW HARRY S. BARR. JR.

g/J [a m ATTORNEY;

United States Patent 0 3,413,677 APRON CLEARERS David M. Ford, Charlotte, Alfred C. Morrow, Lowell,

and Harry S. Barr, Jr., Charlotte, N.C., assignors to Pneumafil Corporation, Charlotte, N.C., a corporation of Delaware Filed Dec. 9, 1963, Ser. No. 328,900 16 Claims. (Cl. 15256.51)

ABSTRACT OF THE DISCLOSURE An apparatus for clearing a moving surface of foreign matter by supporting a wiping apron for movement on a support adjacent the surface to be cleared, with the apron contacting and moving with respect to the support and the surface to be cleared. The coefficient of friction between the support and the apron is greater than the coefficient of friction between the surface to be cleared and the apron so that the movement of the surface to be cleared coupled with the force with which the apron is forced against the surface imparts movement to the apron which is restricted by the friction between the support and the apron, thereby producing a wiping action on the surface to be cleared.

Background of the invention This invention relates to the clearing of foreign matter from a moving surface of processing equipment in which the moving surface tends to become contaminated by the materials being processed. More particularly, the invention provides improved means for clearing the processing rolls of textile equipment such as draw frames, spinning frames, roving frames, and the like, and has specific utility in effecting simultaneous clearing of adjacent bottom rolls of a draw frame.

A variety of clearers have been evolved for use in maintaining the surfaces of the processing rolls of textile equipment free of lint, fly, and the like foreign matter tending to accumulate on these roll surfaces as a result of the passage thereover of the textile fibers being processed. Generally, these clearers comprise a wiper member arranged to contact the surface to be cleared, with the wiper being maintained stationary with respect to the relatively moving surface so that any material collecting on the surface to be cleared is engaged by the wiper member with the effect that the foreign matter is dislodged from the surface to be cleared. However, in utilizing such apparatus it is found that a condition referred to as eyebrowing occurs in which a mass of cleared fibers attains a position of static equilibrium between the cleared surface and the wiper member. Additional problems are encountered when it is desired to clear a plurality of relatively closely spaced moving surfaces such as on the bottom rolls of a draw frame, where space requirements prevent easy access to the rolls interfering with the necessary periodic removal of the eyebrows, and additionlly interfering with the desired positioning of the clearer members with respect to the rolls.

Summary of the invention It is with the above problems and desiderata in mind, that the present means, including apparatus, have been evolved, means providing for the clearing of a moving surface in a fashion such as to prevent the occurrence of eyebrowing, and serving to insure the positive displacement of the cleared material away from the surface to be cleared. The novel means additionally implement the clearing of a plurality of moving surfaces arranged in a relatively small and inaccessible area.

Patented Dec. 3, 1968 It is accordingly among the primary objects of this invention to provide improved means for clearing foreign matter from a moving surface.

A further object of the invention is to provide improved clearing means serving to positively displace the cleared material from the cleared surface.

An additional object of the invention is to provide means for clearing a moving surface in which the cleared material is prevented from attaining a state of static equilibrium with respect to the cleared surface.

A further object of the invention is to provide improved roll clearing means in which the wiping elements are substantially self-cleaning, minimizing the required care of an operator.

Another important object of the invention is to provide an improved clearer for the rolls of textile processing machinery in which the clearer is subject to positioning in operative relationship with respect to the bottom rolls of the machinery.

Another object of the invention is to provide improved roll clearing means adapted for ready positioning in a relatively restricted area with respect to the rolls to be cleared.

These and other objects of the invention which will become hereafter apparent are achieved by provision of an improved clearer comprising a clearer support having two spaced slide surfaces. Arranged over the clearer support for sliding movement with respect thereto is a clearer apron in the form of a sleeve of a resilient wall tube of rubber or the like natural or synthetic material. The in terior dimensions of the tube forming the apron are such as to accommodate the clearer support with spacing between the interior wall of the apron and the clearer support, except for its points of contact with the spaced slide surfaces. It is preferred that one of the slide surfaces be formed to provide less frictional resistance with respect to movement of the apron thereover than the frictional resistance offered by the other slide surface with respect to the movement of the apron. As a result of this difference in frictional resistance encountered by the interior of the apron in its movement over the clearer support, there will be a tendency for the side walls of the apron to extend, contract, and billow slightly between its points of contact with the support. In use, the clearer support with its associated apron is arranged so that the apron contacts the surfaces to be cleared. In a preferred arrangement, the clearer is employed for clearing the bottom rolls of a draw frame, and is arranged in proximity to two rolls, with the slide surface offering less frictional resistance to the movement of the apron arranged between the rolls to be cleared.

A feature of the invention resides in the formation of the apron with an exterior surface having a lower coefiicient of friction with respect to the surfaces to be cleared than the coefficient of friction between the clearer support and the interior of the clearer apron. As a result of these differences in coeflicients of friction, the apron support serves to retard the movement of the apron with respect to the clearer surface thereby producing a desired wiping action. However, the movement of the surface to be cleared, namely the roll with respect to the clearer apron, acts to move the apron and any foreign matter cleared thereby away from the cleared surface.

An additional feature of the invention resides in the arrangement of the clearer supports so that it contacts the interior of the apron at two spaced points with relatively different degrees of frictional engagement. As a result of this difference in engagement between the support and the apron, the apron is distorted in its movement over the clearer support to produce a stretching, and billowing of the apron providing for a relatively self-cleaning effect,

and insuring the prevention of a static condition of equilibrium in the cleared material.

Brief description of the d awings The specific details of the invention, and the mode of functioning will be made most manifest and particularly pointed out in clear, concise and exact terms in conjunction with the accompanying drawings, wherein:

FIG. 1 is a schematic cross-sectional view through a roll stand, showing the novel clearer arranged to clear the surfaces of two bottom rolls; and

FIG. 2 is a perspective view of the clearer shown in FIG. 1; and

FIG. 3 is an exploded perspective view showing the components of the clearer shown in FIG. 2; and

FIG. 4 is a cross-sectional view taken on line 44 of FIG. 3 through the clearer apron illustrating the details of apron formation; and

FIG. 5 is a perspective view of another embodiment of the clearer in which the clearer support is formed of a unitary extrusion; and

FIG. 6 is a schematic cross-sectional elevation through a roll stand in which the clearer shown in FIG. 5 is shown in operative position to clear the bottom rolls.

Description of the preferred embodiments Referring now more particularly to the drawings, like numerals in the various figures will be employed to designate like parts.

The clearer assembly 10 as shown in the FIGS. 1-3 embodiment of the invention comprises a clearer support 11 formed by a bar member 12, which is rectangular in cross-section. L-shaped brackets 14 and are secured to the bar 12 at a spaced distance apart. Extending between the upstanding legs of the brackets 14 and 15 as viewed in FIGS. 2 and 3 is a rod 16.

Apron 18 is formed from a hollow tube of resilient material such as rubber, neoprene, or the like natural or synthetic material suitable as a wiping member for the surface and materials to be cleared. The apron 18 is arranged over the clearer support to ride over rod 16 between the upstanding legs of brackets 14 and 15, as viewed in FIG. 2. The apron 18 is of a cross-sectional dimension such that it fits loosely over the clearer support 11, as best seen in FIG. 1, and contacts a slide surface 19 formed at the upper perimeter of rod 16, and a slide surface 20, spaced from slide surface 19, and formed at the corner of bar 12, as seen to the left in FIG. 1.

It is preferred that the apron 18 be formed with an interior surface 21 having a relatively higher coefficient of friction with respect to the slide surfaces 19 and of the clearer support 11 than the coefficient of friction of the outer surface 22 of sleeve 18 with respect to the cleared surface. These differences in coefficients of friction may be most readily obtained by forming the sleeve of a laminate construction, as shown in FIG. 4, in which the inner layer of apron 18 is formed of a material such as Armstrong 700, while the outer layer is formed in a material such as Armstrong 750. In practice it isfound by the utilization of material such as the above referred to Armstrong materials, desired coefiicients of friction between the outer surface 22 of the apron 18 with respect to the steel rolls of a draw frame will provide desired results as compared to the coefficient of friction produced by the contact of inner surface 21 with respect to the conventional aluminum materials from which the clearer support is fabricated.

In the embodiment of the invention illustrated in FIGS. 5 and 6, the clearer support has been modified to implement its fabrication of an extrudable material such as aluminum or the like. The sleeve 18 remains the same, and the numerals applied to the FIGS. 5 and 6 embodiments with reference to sleeve 18 have not been changed. The clearer support 51 of the FIGS. 5 and 6 embodiment is formed with a lower bar section 52 which is joined by means of web 53 to upper rod section 56 thereby providing a unitary structure. In order to insure desired relative positioning of apron 18 with respect to the clearer support 51 brackets 54 and 55 are secured to the clearer support 51 at a desired spaced apart distance such as to orient the apron 18 therebetween, as best seen in FIG. 5.

The clearer support rod section 56 provides a slide surface 59 similar to slide surface 19 in FIG. 1, and bar section 52 provides a slide surface 60 similar to slide surface 20 of FIG. 1. The dimensioning of the apron 18 is such as to provide a clearance with respect to clearer support 51 as shown in FIG. 6.

Operation In use, the novel clearer is arranged with respect to surface to be cleared by mounting clearer support 11 or 51 in appropriate supporting brackets on the equipment to be cleared. In the illustrated embodiments of the invention, where the clearer is employed for clearing the bottom rolls of a draw frame, as illustrated in FIGS. f and 6, the clearer is arranged with rods 16 and 56 in proximity to the rolls to be cleared, and so oriented as to bring the apron 18 into contact with these surfaces. The lower end of the clearer support is arranged at a distance from the surfaces to be cleared, and positioned to provide a substantially vertical run at the leaving section of the apron, that is at that section of the apron leaving the rolls and carrying the cleared material.

When the clearer is arranged as described, it will be seen that the rotation of the rolls in contact with the outer surface of apron 18 tends to move the apron 18 over the clearer supports 11 and 51 (depending on which embodiment of the invention is being considered). Since the coefficient of friction between the rolls to be cleared and the outer surface 22 of the apron 18 is less than the coefficient of friction between the inner surface 21 of the apron and the slide surfaces of the clearer support, it will be apparent to those skilled in the art that there will be slippage between the apron and roll surfaces. This slippage provides a wiping action of the apron against the roll surfaces tending to dislodge any foreign matter accumulating on the roll surfaces.

The inner surface of sleeve 18 is contacted by slide surfaces 19 and 20, FIG. 1 (and 59 and 60 in FIG. 6) with the frictional resistance between the inner surface of sleeve 18 and the slide surfaces determining the facility with which the apron may be moved about the clearer support. It will be observed that slide surface 19 is rounded and relatively broad as compared to the relatively sharp slide surface 20 (59 and 60 respectively in FIG. 6). As a result of this difference between the rounded and sharp surface, there is a difference in frictional resistance offered at these two slide surfaces to the movement of the apron. Thus, though the apron may slide relatively freely over the rounded slide surface 19 there is more resistance to the movement of the apron over the slide surface 20. Considering the movement of the apron in the direction of the arrows as illustrated in FIGS. 1 and 6, it will be noted that as the apron 18 is moved between slide surface 20 and slide surface 19 (60 and 59 in FIG. 6) it will tend to stretch due to the forces exerted on the apron by the rolls being cleared. On the other hand that portion of the apron between the slide surface 19, and the roll to the right of slide surface 19, as viewed in FIGS. 1 and 6, and slide surface 20 will tend to billow and flex due to the resistance to movement of the apron over slide surface 20. The result of this flexing and billowing of the apron as it carries the foreign matter from the cleared rolls serves to dislodge the cleared material from the apron surface, thus providing a self-cleaning action,-and minimizing any tendency towards eyebrowing.

It is thus seen that a simple clearer has been provided having particuar utility in the clearing of foreign matter from a moving surface arranged in a relatively small or inaccessible area, such as the bottom rolls of the draw frame. The action of the clearing element, in this instance the apron, is such as to provide a self-cleaning action for the apron, and a disturbance of any equilibrium condition which the foreign matter cleared may attain.

The above disclosure has been given by way of illustration and elucidation, and not by way of limitation, and it is desired to protect all embodiments of the herein disclosed inventive concept within the scope of the appended claims.

What is claimed is:

1. In equipment having a moving surface, means for clearing said surface of foreign material, said means comprising: stationary supporting means adjacent the surface to be cleared; continuous wiping apron means slidably mounted on said supporting means and contacting the surface to be cleared, said supporting means offering greater frictional resistance to the passage of said wiping means thereover than offered by the surface to be cleared to the passage thereover of said wiping means.

2. Means for clearing a moving surface of foreign material, as in claim 1, in which said supporting means comprise two spaced slide means in contact with said wiping means.

3. Clearing means as in claim 2 in which said slide means offer different frictional resistance to the movement of said wiping means thereover.

4. Clearing means as in claim 1 in which said wiping means is mounted to move in a substantially vertical plane after leaving the cleared surface.

5. In equipment having a moving surface, apparatus for clearing said moving surface of foreign material, said apparatus comprising: a fixed clearer support; spaced slide surfaces on said clearer support; and a continuous wiping apron slidably arranged over said clearer support on said spaced slide surfaces in contact with said moving surface said spaced slide surfaces offering greater frictional resistance to the passage of said wiping apron thereover than offered by the surface to be cleared to the passage thereover of said wiping apron.

6. Apparatus as in claim 5 in which said supporting member comprises: a bar having a relatively sharp edge defining a slide surface for said apron; and a rod secured to said bar defining a relatively smooth slide surface for said wiping apron.

7. Apparatus as in claim 6 in which said clearer support is formed as a unitary extrusion comprising said bar and said rod.

8. Apparatus as in claim 5 in which said apron comprises a tube having an inner layer formed of a material having a relatively high coefiicient of friction with respect to the slide surfaces as compared to an outer layer of said tube formed of material having a relatively lower coefficient of friction with respect to the surface to be cleared.

9. In processing equipment having top rolls and bottom rolls, a clearer for the bottom rolls, said clearer comprising: a fixed support; a slide surface and said support; a continuous wiping apron arranged over said support and slidable on said slide surface with an exterior surface of said apron in contact with the rolls to be cleared, said apron having an exterior surface with a lower coefiicient of friction with respect to the roll than the coeflicient of friction between the interior of the apron and said slide surface.

10. Apparatus as in claim 9 in which said support is formed with two spaced slide surfaces, one of said surfaces in proximity to the roll to be cleared having a lower coefiicient of friction with respect to the apron than the coefficient of friction of the other slide surface with respect to the apron.

11. Apparatus as in claim 10 in which said support comprises: a bar, a corner of which forms said high coefiicient of friction slide surface; and a rod, a portion of the surface of which forms the low coefiicient of friction slide surface.

12. Apparatus as in claim 11 in which said support is formed as an extrusion.

13. Apparatus as in claim 9 in which said apron is mounted on said support to move along a vertical path after leaving the last of the rolls to be cleared thereby.

14. In equipment having a moving surface, apparatus for clearing said moving surface of foreign material, said apparatus comprising: a stationary elongate support positioned adjacent the surface to be cleared; a smooth rounded slide surface on said support; a relatively sharp slide surface on said support; and an endless wiping apron slidably arranged over said support with the interior surface of said apron contacting said slide surfaces, and the exterior of said apron frictionally engaging the moving surface to be cleared for movement thereby, the coefficient of friction between the interior of said apron and said slide surfaces being greater than the coefficient of friction between the exterior of said apron and the surface to be cleared, said apron dimensioned to provide a slack billowing surface in its movement between said rounded slide surface and said sharp slide surface.

15. Apparatus, as in claim 14, in which said support with said slide surfaces is formed as an extrusion.

16. Apparatus, as in claim 14, in which said support comprises a rectangular rod and a circular rod.

References Cited 139,312 2/1953 Sweden.

MORRIS O. WOLK, Primary Examiner.

J. ZATARGA, Assistant Examiner. 

